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Over the past decade, the capability of double-stranded RNAs to interfere with gene expression has driven new therapeutic approaches. Since small interfering RNA (siRNAs, 21 base pair double-stranded RNA) was shown to be able to elicit RNA interference (RNAi), efforts were directed toward the development of efficient delivery systems to preserve siRNA bioactivity throughout the delivery route, from the administration site to the target cell. Here we provide evidence of RNAi triggering, specifically silencing c-myc protooncogene, via the synthesis of a library of novel multifunctional gold nanoparticles (AuNPs). The efficiency of the AuNPs is demonstrated using a hierarchical approach including three biological systems of increasing complexity: in vitro cultured human cells, in vivo invertebrate (freshwater polyp, Hydra), and in vivo vertebrate (mouse) models. Our synthetic methodology involved fine-tuning of multiple structural and functional moieties. Selection of the most active functionalities was assisted step-by-step through functional testing that adopted this hierarchical strategy. Merging these chemical and biological approaches led to a safe, nonpathogenic, self-tracking, and universally valid nanocarrier that could be exploited for therapeutic RNAi.

In this work we propose the use of Social Network Analysis to understand the positioning of the concept of Open Innovation in the literature, offering thereby a complementary approach to existing literature review up to now. The main motivation of this network analysis is to contribute to the understanding of the concept of Open Innovation, with its spread to different areas of knowledge over the years and its relationship with other concepts in the literature. Some 403 articles published in the database of the Science Direct during the years 2003 to 2011 were analyzed. The data was collected separately by year, considering the following information: journals in which the articles were published; countries of origin of the articles’ authors, keywords of these articles and year of publication. The results reveal the intense growth of the use of the words "Open Innovation" in articles from different areas of knowledge, as well as its increasing interconnection with other concepts, allowing the understanding of its diffusion in the literature.

Theoretical transition energies and probabilities for He-, Li and Be-like Praseodymium ions are calcu- lated in the framework of the multi-configuration Dirac-Fock method (MCDF), including QED corrections. These calculated values are compared to recent experimental data obtained in the Livermore SuperEBIT electron beam ion trap facility [1].

The lifetime of the 1s22s3p 3P0 level of selected Be-like ions, from Z = 5 to Z = 92, is calculated using the multiconfiguration Dirac-Fock method including QED corrections. Full correlation up to the 4f subshell in both initial and final levels for all possible decay modes was included. The results are in reasonable agreement with the scarce existing experimental and theoretical data.

Tuberculosis (TB) remains one of the most serious infectious diseases in the world and the rate of new cases continues to increase. The development of cheap and simple methodologies capable of identifying TB causing agents belonging to the Mycobacterium tuberculosis Complex (MTBC), at point-of-need, in particular in resource-poor countries where the main TB epidemics are observed, is of paramount relevance for the timely and effective diagnosis and management of patients. TB molecular diagnostics, aimed at reducing the time of laboratory diagnostics from weeks to days, still require specialised technical personnel and labour intensive methods. Recent nanotechnology-based systems have been proposed to circumvent these limitations. Here, we report on a paper-based platform capable of integrating a previously developed Au-nanoprobe based MTBC detection assay-we call it {"}Gold on Paper{"}. The Au-nanoprobe assay is processed and developed on a wax-printed microplate paper platform, allowing unequivocal identification of MTBC members and can be performed without specialised laboratory equipment. Upon integration of this Au-nanoprobe colorimetric assay onto the 384-microplate, differential colour scrutiny may be captured and analysed with a generic {"}smartphone{"} device. This strategy uses the mobile device to digitalise the intensity of the colour associated with each colorimetric assay, perform a Red Green Blue (RGB) analysis and transfer relevant information to an off-site lab, thus allowing for efficient diagnostics. Integration of the GPS location metadata of every test image may add a new dimension of information, allowing for real-time epidemiologic data on MTBC identification.

Aims: Our aim is to explore whether gold nanoparticles (AuNPs) functionalized with a carboxylated polyethylene glycol (PEG) and protamine (AuNP@PEG@Prot) can modulate - enhance or restrain - DNA condensation, altering DNA conformation and inducing structural changes. Understanding how these nanoconjugates modulate DNA structure, size and shape of DNA condensates, and enable control over the resulting 3D structures is of major biological and therapeutic importance. Materials & methods: Citrate-AuNPs were covered with a dense layer of a hetero-functional octa(ethylene glycol) (SH-EG(8)-COOH). Conjugation of protamine to the AuNP@PEG was achieved by taking advantage of the carboxylated surface previously generated on the surface of the NP and the remaining amino groups from the protamine, using carbodiimide and N-hydroxysulfosuccinimide coupling reactions. Results & conclusion: AuNP@PEG@Prot modulates the structure and topology of DNA, not only for condensation, but also for decondensation, via formation of higher quantities of dimers and multimers, when compared with AuNP@PEG and free protamine.

The surface chemistry of gold nanoparticles (AuNPs) plays a critical role in the self-assembly of thiolated molecules and in retaining the biological function of the conjugated biomolecules. According to the well-established gold-thiol interaction the undefined ionic species on citrate-reduced gold nanoparticle surface can be replaced with a self-assembled monolayer of certain thiolate derivatives and other biomolecules. Understanding the effect of such derivatives in the functionalization of several types of biomolecules, such as PEGs, peptides or nucleic acids, has become a significant challenge. Here, an approach to attach specific biomolecules to the AuNPs (∼14 nm) surface is presented together with a study of their effect in the functionalization with other specific derivatives. The effect of biofunctional spacers such as thiolated poly(ethylene glycol) (PEG) chains and a positive peptide, TAT, in dsRNA loading on AuNPs is reported. Based on the obtained data, we hypothesize that loading of oligonucleotides onto the AuNP surface may be controlled by ionic and weak interactions positioning the entry of the oligo through the PEG layer. We demonstrate that there is a synergistic effect of the TAT peptide and PEG chains with specific functional groups on the enhancement of dsRNA loading onto AuNPs.

Measuring RNA synthesis and, when required, the level of inhibition, is crucial towards the development of practical strategies to evaluate silencing efficiency of gene silencing approaches. We developed a direct method to follow RNA synthesis in real time based on gold nanoparticles (AuNPs) functionalized with a fluorophore labeled hairpin-DNA, i.e. gold-nanobeacon (Au-nanobeacon). Under hairpin configuration, proximity to gold nanoparticles leads to fluorescence quenching; hybridization to a complementary target restores fluorescence emission due to the Au-nanobeacons' conformational reorganization that causes the fluorophore and the AuNP to part from each other, yielding a quantitative response. With this reporter Au-nanobeacon we were able to measure the rate of in vitro RNA synthesis ( 10.3. fmol of RNA per minute). Then, we designed a second Au-nanobeacon targeting the promoter sequence (inhibitor) so as to inhibit transcription whilst simultaneously monitor the number of promoters being silenced. Using the two Au-nanobeacons in the same reaction mixture, we are capable of quantitatively assess in real time the synthesis of RNA and the level of inhibition.The biosensor concept can easily be extended and adapted to situations when real-time quantitative assessment of RNA synthesis and determination of the level of inhibition are required. In fact, this biosensor may assist the in vitro evaluation of silencing potential of a given sequence to be later used for in vivo gene silencing.

Tuberculosis remains one of the most serious infectious diseases worldwide requiring new tools to circumvent current molecular diagnostics limitations. Nanodiagnostics, i.e. nanotechnology based diagnostics, may do just that by decreasing the time needed for the molecular characterisation of the infecting agent, and allowing for miniaturisation and portability for point-of-need adapted to remote regions without suitable lab equipment.

In the last decade the use of nanomaterials has been having a great impact in biosensing. In particular, the unique properties of noble metal nanoparticles have allowed for the development of new biosensing platforms with enhanced capabilities in the specific detection of bioanalytes. Noble metal nanoparticles show unique physicochemical properties (such as ease of functionalization via simple chemistry and high surface-to-volume ratios) that allied with their unique spectral and optical properties have prompted the development of a plethora of biosensing platforms. Additionally, they also provide an additional or enhanced layer of application for commonly used techniques, such as fluorescence, infrared and Raman spectroscopy. Herein we review the use of noble metal nanoparticles for biosensing strategies-from synthesis and functionalization to integration in molecular diagnostics platforms, with special focus on those that have made their way into the diagnostics laboratory.

We study the most important processes for the creation of excited states in He-like through C- like praseodymium ions from the ions ground configurations, leading to the emission of K X-ray lines. Theoretical values for inner-shell excitation and ionization cross sections, transition probabilities and energies for the deexcitation processes, are calculated in the framework of the multi-configuration Dirac- Fock method, including QED corrections. Using these calculated values, a theoretical Kα X-ray spectrum is obtained, which is compared to recent experimental data obtained in the Livermore Super-EBIT electron beam ion trap facility.

Nanotechnology provides new tools for gene expression analysis that allow for sensitive and specific characterization of prognostic signatures related to cancer. Cancer is a multigenic complex disease where multiple gene loci contribute to the phenotype. The ability to simultaneously monitor differential expression originating from each locus allows for a more accurate indication of degree of cancerous activity than either locus alone. Metal nanoparticles have been widely used as labels for in vitro identification and quantification of target sequences. Here we describe the synthesis of nanoparticles with different noble metal compositions in an alloy format that are then functionalized with thiol-modified ssDNA (nanoprobes). We also show how to use such nanoprobes in a non-cross-linking colorimetric method for the direct detection and quantification of specific mRNA targets, without the need for enzymatic amplification or reverse transcription steps. The different metals in the alloy provide for distinct absorption spectra due to their characteristic plasmon resonance peaks. The color multiplexing allows for simultaneous identification of several different mRNA targets involved in cancer development. Comparison of the absorption spectra of the nanoprobes mixtures taken before and after induced aggregation of metal nanoparticles allows to both identify and quantify each mRNA target. We describe the use of gold and gold:silver-alloy nanoprobes for the development of the non-cross-linking method to detect a specific BCR-ABL fusion gene (e.g., e1a2 and e14a2) mRNA target associated with chronic myeloid leukemia (CML) using 10 ng μL -1 of unamplified total human RNA. This simple methodology takes less than 50 min to complete after total RNA extraction with comparable specificity and sensitivity to the more commonly used methods.

Hierarchical wrinkling on elastomeric Janus spheres is permanently imprinted by swelling, for different lengths of time, followed by drying the particles in an appropriate solvent. First-order buckling with a spatial periodicity (λ11) of the order of a few microns and hierarchical structures comprising of 2nd order buckling with a spatial periodicity (λ12) of the order of hundreds of nanometers have been obtained. The 2nd order buckling features result from a Grinfeld surface instability due to the diffusion of the solvent and the presence of sol molecules.

The introduction of an ester group in the flavylium core allowed the reversible conversion between two different flavylium compounds each one exhibiting its own reaction network. An unidirectional switching cycle between 7-diethylamino-2-(4-(methoxy-carbonyl)phenyl)-1-benzopyrylium and 2-(4-carboxyphenyl)-7-diethylamino-1-benzopyrylium was achieved by means of alternate acid and base stimuli. Addition of base to a methanolic solution of the ester derivative gives rise to the trans-chalcone of the parent carboxylic acid, which upon acidification of the solution forms the respective flavylium cation. This species esterifies under very acidic conditions to restore the original methyl ester derivative. The chemical reaction networks of both compounds were fully characterized from their thermodynamic and kinetic aspects, by a series of pH jumps followed by UV-vis absorption and emission spectroscopy, stopped flow and H-down arrow NMR. The crystal structure of the trans-chalcone of the ester derivative was unveiled showing a supramolecular structure involving hydrogen bonding.